Western blotting of IgM with extracts of normal human kidney.

IgM in the plasma of patients with WAIHA and healthy blood donors was interacted at 20 μg/mL with a soluble extract of kidney antigens, as described in Materials and Methods. Lanes 1 to 10: IgM of patients; lanes 15 to 24: IgM of healthy blood donors; lanes 12 and 13: normal reference IgM (IVIgM); lanes 11 and 14: secondary anti-Fcμ antibody alone.